Acute flaccid myelitis (AFM) is a uncommon situation that impacts the nervous system and has a few 2% restoration charge. The starkness of a medical statistic like that is brutal, and much more so when it pertains to the well being of your personal kids, however this was what Bodo Hoenen and his household had been dealing with in the summertime of 2016 when their five-year-old daughter, Lorelei, was identified with AFM.
The situation significantly impacts the spinal column and in Lorelei’s case it had paralysed her left shoulder and left arm. “The prognosis was that the one factor that may assist was occupational remedy and physiotherapy,” says Hoenen, “however wanting on the outcomes, again then, there have been solely two youngsters that had had any vital restoration…”
Hope was wanted and it was sparked by a mission the household noticed within the hospital: “Researchers had been strapping on an exoskeleton swimsuit to paraplegic people and offering them the biofeedback with the swimsuit,” recollects Hoenen. “Additionally they supplied visible suggestions by including a VR headset displaying them the precise motion of the arms. With the headset, you’d see your self strolling after which really feel your physique strolling because the exoskeleton swimsuit was transferring your physique and this is able to drive the mind to assume ‘Okay, I’m going to stroll now’ and they might decide up these alerts from the mind and translate them into messages to manage the exosuit and VR.”
After consulting specialists, Hoenen theorised that as a substitute of hooking sensors to the mind they wanted to hook sensors on to the biceps muscle in Lorelei’s arm: “We knew there have been at the very least very weak alerts going to the muscle and we had been hoping to choose these up and hoping that forcing her to proceed sending alerts to her muscle groups would assist that rehabilitation course of.”
Hoenen knew that in all probability one of the best ways to do that was to construct some type of robotic prosthetic arm, however he had an issue: he had no thought do it. That’s when he and Lorelei determined to ask the world. “We determined to leverage the collective intelligence of everybody round us,” says Hoenen.
So, after sifting via all the data they might discover and speaking to different mother and father with kids that had AFM, Bodo and Lorelei started working with a easy first design – they wished to 3D-print the braces and by some means purchase an actuator motor to assist pull the arm up and down. However earlier than they obtained too far into the mission, they determined to file some movies to ask specialists for assist.
The response was “pleasantly shocking”, says Hoenen. Inside a few weeks they’d had Actuonix donating actuators whereas, amongst many helpers, they’d obtained help from specialists in battery tech and electronics from South Africa and Germany respectively, and had a full scan of Lorelei’s arm finished. It wasn’t lengthy earlier than a prototype was made, adopted by a 3D-printed sleeve in PLA.
Nonetheless, the largest concern they confronted was choosing up the muscle sign from Lorelei’s arm. They found that it was very tough to filter and normalise the sign and set a threshold that triggered the actuator. Hoenen discovered there was little or no distinction within the sign between when her arm was at relaxation or energetic. As they tried to set a threshold, in addition they seen that the actuator might be triggered by a finger twitch and even Lorelei’s coronary heart, in order that they put out one other video asking for assist.
Hoenen pitched the concept that the uncooked sign might be run via machine studying or sample recognition software program to trace down a singular sign. Quickly after posting their video, they got here throughout a agency known as Coapt that makes use of sample recognition software program to assist amputees use prosthetic limbs. The corporate has a proprietary system that makes use of 17 sensors to trace the muscle alerts. The software program interprets the alerts it finds into corresponding actions on a digital arm. Coapt gave the household an analysis unit to allow Lorelei to practise and decide up the arm alerts, which meant Hoenen might lastly create a working mannequin.
Whereas some producers had been extremely beneficiant, Hoenen says he encountered a shocking quantity of negativity from others: “Lots of them saved mentioning ‘is that this FDA authorized?’ […] From my perspective, I don’t care. That is about my daughter, I need this resolution to work. These things that you just’ve obtained prices $50,000. I simply can’t afford that and the know-how that you’ve isn’t all that intelligent, so why don’t we open-source this and expedite the innovation that occurs with what we’ve obtained and this may create a greater world for all of us together with your small business mannequin?” Sadly, many medical producers aren’t prepared to even think about experimenting with open fashions but. “Open innovation drives innovation exponentially [compared to] closed, however they failed to essentially grasp that,” says Hoenen.
In January of this yr, Lorelei got here as much as her mother and father and stated, “Hey look what I can do,” and was in a position to transfer her arm up and down unassisted. Since then she hasn’t wanted to make use of the prosthetic and whereas Hoenen says it’s not one thing he desires to take additional himself, he’s serving to different mother and father and making an attempt to sort out “a number of the core challenges nonetheless to beat.” These embrace creating bridge software program between a system of 17 electrodes and the gadget, the Raspberry Pi on this occasion, and getting the right construct for the arm sleeve that homes the electrodes.
Speaking concerning the expertise, Hoenen is cautious to downplay the know-how. He’s additionally pragmatic over whether or not the arm made that a lot of a distinction to Lorelei’s restoration: “In the meanwhile, we solely have a pattern measurement of 1,” he concedes. At Medication X Stanford in September, Hoenen most popular to explain the expertise as a narrative of “tangible hope, the place we’d have been spectators with out this mission”. Nonetheless, different mother and father who’ve kids identified with AFM are utilizing the mission to construct robotic prosthetics and difficult that 2% restoration charge.
Bodo and Lorelei’s mission is documented and open-sourced on www.ourkidscandoanything.com with movies of the journey, guides for constructing the arm itself and extra particulars of the important thing remaining challenges.
(This function was first revealed in concern 184 of Linux Consumer & Developer).